Saturn Nebula
From Wikipedia, the free encyclopedia
| Planetary nebula | Lists of nebulae |
|---|---|
| Image:Planetary nebula NGC7009.jpg
NGC 7009, the Saturn Nebula. |
|
| Observation data (Epoch J2000.0) |
|
| Right ascension | 21h 04m 10.877s[1] |
| Declination | -11° 21′ 48.25″[1] |
| Distance | 2000-4000 ly (See article) |
| Apparent magnitude (V) | 12.8[1] |
| Apparent dimensions (V) | 60 × 40 arcsecs |
| Constellation | Aquarius |
| Physical characteristics | |
| Radius | 0.2-0.4 ly |
| Absolute magnitude (V) | 2.5 to 1 |
| Notable features | - |
| Other designations | NGC 7009[1] |
The Saturn Nebula (also known as NGC 7009) is a planetary nebula in the Aquarius constellation. It was discovered by William Herschel on September 7, 1782 using his 20ft (focal length) reflector (telescope) at Slough England and one of his earliest discoveries in his sky survey. The nebula was originally a low-mass star that transformed into a rather bright white dwarf star, magnitude 11.5. The Saturn Nebula gets is name from its superficial resemblance to the planet Saturn with its rings nearly edge on to the observer. It was so named by Lord Rosse in the 1840s, when telescopes had improved to the point that its Saturn like shape could be discerned. William Henry Smyth said that the Saturn Nebula is one of Struve's 9 "Rare Celestial Objects."
The distance to the Saturn nebula is not known very well because there are no reference stars in its neighborhood that have been detected and could be used to accurately gauge its distance. Therefore, any distance is somewhat suspect. Hynes estimates it to be 2,400 light-years distance from earth. In 1963, O'Dell estimated the distance to be 3,900 light-years.
The object is on many 'best of' observing lists, including: SAC 110 best NGC object list, RASC's Finest N.G.C. Objects Objects, and The Caldwell Catalog #55.
